tree eab782e5653e5513eb554d5f4910fcf52dab39df
parent 1ff9b7ffa653de1d25c5e013d731054815b13e86
author Vlad Tsyrklevich <vtsyrklevich@chromium.org> 1511965939 +0000
committer Chromium commit bot <commit-bot@chromium.org> 1511965939 +0000

[CFI] Enable type generalization for LCMS

Control Flow Integrity [1] indirect call checking verifies that function
pointers only call valid functions with a matching type signature. This
condition can be too strict, a common form of 'abstraction' relies on
function pointers being cast to generalize argument pointer types to
void*.

In LCMS these failures occur because of casts of function pointers called
as both _cmsInterpFn16 (cmsInterpFunction.Lerp16) and _cmsOPTeval16Fn (as
an argument to _cmsPipelineSetOptimizationParameters) types making it
difficult to refactor out easily. Instead, enabling the type
generalization build config weakens the type checking performed for
CFI-icall to accomodate this common type of casts.

[1] https://www.chromium.org/developers/testing/control-flow-integrity

Bug: 785442
Change-Id: Ib42fb1b4e152d5042b170698c2707ebb9e0cc1ee
Reviewed-on: https://pdfium-review.googlesource.com/19250
Commit-Queue: dsinclair <dsinclair@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>